Complex antimony compounds and process of making same



-Patented May 17, I

' UNITED STATES v y 1,628,838 PATENQT- OFFICE.

I HANS HAHL, or ELBnarELn, mean COLOGNE-ON-THE-RHINE, GERMANY, AssIGNon 'ro wmrnnor cannon. company, me, or new YORK, 11. Y.'

oom'rtnx ANTIMONY couroumds AND raocnss OF'MAKING sum.

, No Drawing. .Application filed Iarch 29, 1926, Serial No. 98,272, and in Germany June 6, 1925.

com mind of such a. polyphenol as contains two ydroxyl groups in the ortho-position to each other, is caused to interact either with a neutral salt of .a-carboxylio acid which con tains in the molecule easily migratory hydro-V gen atoms as, for example, malomc acid,

levulinic acid or diacet-yl succinic acid:

The new compounds are in most cases colorless or only slightly colored substances, the neutral aqueous solutions of which are not recipitated byalkalies but are precipitatedi by alkali metal sulphides. They possess outstandin specific acting properties and are intended to findapplication in therapy. Their aqueous solutions possess no irritant efiect and can be sterilized at 100 C. The followingexamplesserye to illustrate the invention '1 w EwampZe-1.30 parts by weightof malonic acid are dissolved in 500 parts of water and neutralized with 100 parts 'of-cr stalline sodium carbonate, to, the clear so ution are then added '30 parts by weight of antimonyl pyrocatechin (Centralblatt 1898, II page 598) and heating is effected for some time. The greater part of the antimonyl pyrocatechin passes into solution, whereupon I the liquid is filtered and the filtrate evaporated until the separation of crystals commences. On subsequent rapid, cooling, the sodium salt of the complex antimonyl pyrocatechin malonic acid separates completely. After filtration the product may be recrystallized from alcohol-acetone, as practically colorless needles, which are easily soluble in water with a neutral reaction. From the aqueous solution alkali metal sulphides precipitate the orange-red antimony sulphide.

Ewa/mple 2.To 30 parts by weight of malonic acid, a solution of 80 parts by weight of crystalline sodium carbonate in 250 parts of water is gradually added, and.

the clear solution is then heated for some time with 28 parts by weightof antimonyl gallic acid' (Centralblatt 1898, II page 599) when the greater part of the antimonyl gallic acid passes into solution. The liqu1d is filtered and the acid filtrate evaporated until the separation of crystals commences and then cooled. The acid sodium salt of a complex antimonyl gallic-malonic acid soon separates, being obtained after filtration and drying in the form of a bright powder. With'sodium carbonate, it is easily converted in aqueous solution into the neutral salt, which is stable towards alkalies, but gives a precipitate of antimony sulphide with alkali metal sulphides.

Example 3-20 parts by weight of levulinic acid are neutralized with a solution of 25 parts by weight of crystalline sodium carbonate in 200 parts of water and heated for some time with the addition of 20 parts by weight of antimonyl pyrocatechiu, the greater part of the latter passing into solution. The funther treatment follows that described in Example 1. The sodium salt of a complex antimonyl pyrocatechinlevulinic acid, after recrystallization from alcoholacetone and drying forms a yellowish-white powder, which is easily soluble in water with a practically neutral reaction. The aqueous solution is stable towards alkalies but alkali metal sulphides precipitate antimony sul- I phide.

Ewample 4.50 parts by weight of crys talline sodium carbonate are dissolved in 300 'almost white powder. The product may be easily converted in aqueous solution into the neutral salt by means of sodium carbonate. i ]i-claim:- v

1. The process for the manufacture of complex antimony compounds, which process consists in causing an antimonyl com ound of a polyphenol containing two hy roxyl groups in ortho-positionto each other to interact with a neutral salt ofa carboxylic acid containing in'the molecule easily migratory hydrogen atoms.

2. The new complex antimony compounds derived from a" carboxylic' acid containing in the molecule easily migrating hydrogen atoms and an antimonyl compound of a polyphenol containing two hydroxyl groups in ortho-position to each bther, being generally in the form of their alkali metal salts colorless or slightly colored substances, the neutral'aqueous solutions of which are not precipitated by alkalies but are. precipitated by alkali metal sulfides. Possessing outstanding specific actin properties, being intended to find application in therapy, their aqueous solutions possessing no irritant effect agd being capable of being sterilized at 100 3. A new complex antimony compound as defined in claim 2, being derived from malonic acid and an antimonyl pyrocatechin.

In testimony whereof I have hereunto set my hand.

HANS HAHL. 

